Application of cutting mechanics to reciprocating sawing

Thomas Paul James, Marquette University

Abstract

In the handling of bulk metals, it is common practice to use a sawing machine, such as a bandsaw or power hacksaw to reduce the workpiece to a manageable size for downstream processing. Recently, stationary power hacksaws have been replaced with more versatile portable electric reciprocating saws. These machines differ from bandsaws and power hacksaws in that they are portable, light-weight, and saw by rapidly reciprocating a blade over a short stroke length. In industrial applications, the speed of metal sawing is an important economic factor. The mechanics of metal sawing with traditional machines have been described in the literature, but virtually no research has been published on the mechanics of reciprocating sawing. Research was undertaken to describe metal sawing with reciprocating saws by the application of metal cutting mechanics. Cutting rates of metals with a reciprocating saw are dependent upon several process parameters, such as the applied pressure on the saw, the reciprocating speed of the saw blade, and the geometry of the cutting edges. An analytical model was developed to predict the cutting rate of metals with a reciprocating saw. Particular attention was placed on the sawing rates of steel due to their broad commercial usage. The analytical model for reciprocating sawing rates was compared to empirical studies of important process parameters. A wear model for the cutting edges of saw blade teeth was also derived. Using a Design of Experiments technique, a test matrix was developed to determine the significance of applied thrust force and reciprocating speed on cutting rates of steel. Results of analytical predictions from the newly developed sawing model and empirical data compared reasonably well.

This paper has been withdrawn.